python字节流怎么转化成图片

import base64

# 图片转字节
def tu_zi_jie():
 with open('jiu.png','rb') as fp:
 tu = base64.b64encode(fp.read())
 # 生成很长得一串字节流
 print(tu)

if __name__ == '__main__':
 tu_zi_jie()

import base64

# 字节转图片
def zi_tu():
	# 这个就是把上面打印的字节流那过来进行转换图片
	# 因为转换后字符串很长所以我截取了一部分
	b_tu = b'iVBORw0KGgoAAAANS....UhEU'
	tu_b = base64.b64decode(b_tu)
 with open('tu.png', 'wb') as fp:
 fp.write(tu_b)
if __name__ == '__main__':
 tu_zi_jie()